Mixing and spraying apparatus



Feb i4, 1967 H, QANTRELL ET AL 3,304,010

' MIXING AND SPRAYING APPARATUS Filed Aug. 12, 1964 2 Sheets-Sheet 1INVENTORS.

BY W m Feb. M, we? J, H CANTRELL ETAL 3304,@10

MIXING AND SPRAYING APPARATUS 2 Sheets-Sheet 2 Filed Aug. 12, l1964INVENTORS.

United States Patent O 3,304,010 MIXING AND SPRAYING APPARATUS James H.Cantrell and Charles Faro, Riverside, Calif., as-

signors to The Flintkote Company, New York, NY., a corporation ofMassachusetts Filed Aug. 12, 1964, Ser. No. 389,174 7 Claims. (Cl.239-142) This invention relates to apparatus for mixing two streams ofliquid and spraying them from a common nozzle. This invention isparticularly directed to apparatus for mixing and spraying two liquidcomponents which will polymerize at room temperature to form a solidproduct.

An important object of this invention is to provide a novel form ofunitary mixing and spraynig apparatus in which intimate mixing of twocomponent streams is accomplished prior to delivery to a common nozzle.

Another object is to provide a device of this type having improved meansfor cleaning all parts of the apparatus contacted by the mixture, andwithout disassembly of any parts of the mixing apparatus.

A more detailed object is to provide an improved form of power-drivenrotary mixer for use in a spraying gun.

A related object is to provide a novel form of header for delivering twotluid components to the mixing chamber.

Other and more detailed objects and advantages will appear hereinafter.

In the drawings:

FIGURE 1 is a perspective view showing a preferred embodiment of ourinvention.

FIGURE 2 is a side elevation partly in section showing details ofconstruction.

FIGURE 3 is a transverse sectional view partly broken away and taken onlines 3-3 as shown in FIGURE 2.

FIGURE 4 is a transverse sectional View taken substantially on the lines4-4 as shown in FIGURE 2.

FIGURE 5 is a longitudinal sectional view partly broken away and showingan enlargement of the nozzle parts illustrated in FIGURE 2.

FIGURE 6 is an end elevation of the mixer roto-r.

FIGURE 7 is a longitudinal sectional view taken substantially on thelines 7--7 as shown in FIGURE 6.

FIGURE 8 is a perspective View, on Ia smaller scale, showing one of thering parts used to construct the mixer rotor.

Referring to the drawings, the housing generally designated 10 includesa first housing portion 11 containing axially spaced bearings 12 and 13for supporting the rotary drive shaft 14. The housing 10 also includesthe second housing portion 15 containing the mixing chamber 16 andconnected to the first housing portion 11 by means of threads 17. Anair-motor assembly 20 of conventional design has a stub shaft 21connected by threads 22 and a transverse pin 23 to the drive shaft 14.The enclosing shell 25 of the air motor 20 has a projection 26 whichextends into one end of the housing portion 11 and is clamped inposition by means of the split ears 27 Iand clamp bolt 28 (see FIGUREl).

Drive shaft 14 extends into the housing portion 15 through a rotary sealassembly 30, which includes the rotary portion 30a tixed to the shaft 14and engaging the side face of the stationary portion 30b fixed withinthe housing portion 11. A mixer rotor generally designated 33 is fixedon the forward portion of the drive shaft 14 'and is clamped ybetween acollar 34 and the nut 35. From this description, it will be understoodthat the air motor turns the drive shaft 14 and that the drive shaft 14turns the rotor 33 within the mixing chamber 16.

A lateral inlet opening 36 is provided in the housing portion 15,forward of the rotary seal 30 and communi- Mice eating with the mixingchamber 16. A header 37 is connected to this inlet opening 36 by meansof the threaded fitting 38. This header 37 has a central dischargeopening 39 connected to the fitting 38 and has four parallel inlet ports41, 42, 43, and 44. The port 41 for liquid base material is connected tothe air port 44 by internal passage 45 and -connected to the outlet port39 by internal passage 46. The port 42 for catalyst is connected to thecleaning solvent port 43 by internal passage 47 and is connected to theoutlet port 39 by internal passage 48. Polymerizable liquid material,for example, tolylene diisocyanate, is delivered under pressure to inletport 42 through conduit 51, valve 52, and ttings 53. Liquid basematerial or copolymer, for example, hydroxyl-rich polyester, isdelivered under pressure to inlet port 41 through conduit 54, valve 55,and through ittings similar to those shown at 53. Valves 52 and 55 arearranged to be operated in unison by means -of a common operating handle56. Cleaning solvent under pressure is delivered to port 43 throughconduit 58, valve 59, and fitting 60. Air under pressure is delivered toinlet 44 through conduit 61, valve 62, and an inlet fitting similar totting 60. Cleaning solvent valve 59 and air valve 62 are operatedseparately by separate valve handles.

A nozzle assembly generally designated 65 is positioned at the forwardend of the housing part 15 in alignment with the outlet passage 66. Thenozzle assembly 65 includes the ported plug 67 connected to the housingportion 15 by means of threads 68, which serve to hold abutting conicalsurfaces 69 in contact. Mixed reactive materials pass through outlet 66and through the stepped central bore 70, which extends axially throughthe member 67. Additional passages 71 in the member 67 communicate withthe air passage 72 in the forward end of the housing portion 15. Thenozzle head 73 has a central discharge opening 74 through which themixed reactive materials pass from stepped bore 70 and through which airunder pressure passes from the passages 71. The nozzle head 73 is heldin place by means of the retainer ring 75 connected by threads 76 to thehousing portion 15.

The air conduit is connected ot the air passage 72 by means of the tting81. Both of the air conduits 61 and 80 are connected to the crosshead 82upstream from the air motor 20. Air under pressure is supplied throughconduit 84 to the crosshead 82 and is then distributed to the conduit61, to the air motor 20 through ttings 85, and to the air conduitthrough the needle valve assembly 86.

As shown in FIGURES 6-9, the mixer rotor 33 comprises a plurality ofrings 91 and rings 92 positioned in pairs and placed back-to-back.Therrings 91 each have an annular ange 93 provided by the centralopening 94. Blades 95 are integrally formed with the annular flange 93and are circumferentially spaced on the periphery thereof. The blades 95are wedge-shaped, .and each is provided with converging at surfaces 96and 97, which intersect to form a blade edge 98. The rings 92 areidentical to the rings 91, except that the blades project axially in theopposite direction. Thus, as shown in FIGURE 7, the blades 95 on therings 91 project axially to the left while the blades 95 on the rings 92project axially to the right. The blades on adjacent rings arecircumferentially staggered. Tubular spacers 100 are interposed betweeneach pair of rings 91 and 92, and the parts are then brazed together toform a unitary rotor 33. The blade edges 98 are then ground so that thetips of the blades 95 have close running clearance within thecylindrical bore 31 of the mixing chamber 16.

The mixer rotor 33 is installed in the chamber 16 by separating thehousing parts 11 and 15 on the threads 17. A crosspin 102 on the driveshaft 14 (FIGURE 2) projects into a recess 103 (FIGURE 6), provided onone of the ring fianges in orderto key the mixer rotor 33 to the shaft14. The shaft 14 passes through the central openings 94 in the rings 91and 92 and through the central opening in the tubular spacers 100.Rotation of the mixer rotor 33 occurs in the direction of the arrow 104,as shown in FIGURE 6. The wedge-shaped blades 95 act to mix the twomaterials in a thorough and intimate fashion. The materials are admittedinto the mixing chamber 16 through the inlet 36, just in advance of theseal assembly 30, and the materials pass axially through the mixingchamber 16 and emerge throguh the nozzle 65. The intimate mixingachieved by the rotating blades 95 produces a substantially homogeneousproduct which passes through the discharge opening 66 and through thenozzle 65. Very efficient mixing occurs in a very short period of time.

In operation, the device is grasped in one hand by means of the handlegrip 110, which is secured to one end of the air motor 20. The otherhand is used to operate the valve handle 56, which controls the ow ofthe two reactive component streams delivered under pressure to theconduits V51 and 54. The air motor is rotated by a supply of airdelivered through the conduit 84, and the exhaust air is dischargedthrough holes 111 in the ring 112. Spraying of the mixture by means ofthe nozzle 65 is accomplished by air supplied to the nozzle through theneedle valve 86, conduit 80, and passageway 72.

When it is desired to interrupt the spraying operation, the valve handle56 is swung manually to closed position, thereby cutting off the supplyof the reactive materials. Cleaning solvent and air are then passedthrough the header 37 and inlet 36 into the mixing chamber 16 withoutdelay. This is accomplished by manually opening the valves 59 and 62.The solvent cleans all of the internal surfaces of the device which havebeen contacted by both component streams, and this is quicklyaccomplished without shutting off the air motor. The two streams of reactive materials admitted through ports 41 and 42 in the header 37 firstmeet in the discharge opening 39 in the header. The cleaning solvent andair admitted into the header, following simultaneous shutoff of thereactive materials by means of the common handle 56, serve to clean outthe header 37 as well as all of the internal parts downstream from theheader. This is .accomplished quickly without any need for disassemblingthe parts of the tool.

It will be noted that the seal 30 prevents the reactive materials fromreaching the shaft bearings 12 and 13, and that these bearings may besupplied` with lubricants through the conventional fitting 101.

Having fully described our invention, it is to be understood that we arenot to be limited to the details herein set forth, but that ourinvention is of the full scope of the appended claims.

We claim:

1. Mixing and spraying apparatus comprising a housing having acylindrical bore defining a mixing chamber, a mixer rotor mountedcoaxially within said bore, the rotor comprising a plurality of axiallyspaced rings each having a series of wedge-shaped blades fixed on theperiphery thereof, the blades having running clearance within said bore,the blades on adjacent rings being circumferentially staggered, a powerdriven shaft projecting into the bore for rotating the rotor, means forintroducing liquid materials under pressure into the mixing chamber, aspray nozzle assembly mounted on the housing, and a discharge passage inthe housing connecting the mixing chamber to the nozzle assembly.

2. Mixing and spraying apparatus comprising a housing having acylindrical bore defining a mixing chamber, a mixer rotor mountedcoaxially within said bore, the rotor comprising a plurality of axiallyspaced rings each having a series of wedge-shaped blades fixed on theperiphery thereof, the bladeshaving running clearance Within said bore',the blades on adjacent rings being circumferentially staggered, a powerdriven shaft projecting into the bore for rotatingy the rotor, means forintroducing liquid materials into the mixing chamber, a spray nozzleassembly mounted on the housing, a discharge passage in the housingconnecting the mixing chamber to the nozzle assembly, and means forintroducing air under pressure into said nozzle assembly to spray themixture therefrom.

3. Mixing and spraying apparatus comprising a housing having acylindrical bore defining a mixing chamiber, a mixer rotor mounte-dcoaxially Within said bore, a powerdriven shaft projecting into the borefor rotating the rotor, means for introducing Iliquid materials into themixing chamber, a spray nozzle assembly. mounted on the housing, adischarge passage in the housing connecting the mixing chamber to thenozzle assembly, the rotor comprising a plurality of axially spacedrings each having v.a series of wedge-shaped blades xed on the peripherythereof, the blades having running clearance` within said bore, andmeans for introducing air under pressure into said nozzle assembly tospray the mixture therefrom.

4. Mixing and spraying apparatus comprising a housing having acylindrical bore defining a mixing chamber, a mixerrotor mountedcoaxially within said bore, a plurality of axially spaced rings eachhaving a series` of wedgeshaped blades fixed on the .periphery thereof,each blade having surfaces defining an axially extending leading edge,the leading edges of the blades having running clearance within saidbore, the blades on adjacent rings being circumferentially staggered, apower -driven shaft projecting into the bore for rotating the rotor,means for introducing liquid materials into the mixing chamber, a spraynozzle assembly mounted on the housing, a discharge passage in thehousing connecting ythe mixing chamber to the nozzle assembly, and meansfor introducing air under pressure into said nozzle assembly to spraythe mixture therefrom.

5. Mixing Iand spraying apparatus comprising a housing having a`cylindrical bore defining a mixing chamber, a rotor mounted coaxiallywithin the bore, said rotor having a plurality of axially spaced ringseach having a series of wedge-sh-aped blades thereon, a power drivenyshaft extending into the bore for rotating the rotor, means in cludinga nozzle assembly connected to the housing to receive materialsdischarged from the mixing chamber, an inlet passage on the housing fordelivering Imaterials to be mixed into the mixing chamber, a headerhaving a plurality of inlet ports and la single outlet port, meansconnecting the outlet port of the header to the inlet passage to themixing chamber, the header having two internal passageways one extendingfrom a first inlet port to the header outlet and the other extendingfrom a second inlet port to said header outlet, and the header havinganl additional passageway extending from the first inlet port to a thirdinlet port, and means including valve means for controlling ow into eachof said header inlet ports.

6. Mixing and spraying apparatus comprising a housing having acylindrical boredefining a mixing chamber, a rotor mounted coaxiallywithin the bore, said rotor having a plurality of axially spaced Iringseach having a series of wedge-shaped blades thereon, a power drivenshaft extending into the bore for rotating the rotor, means including anozzle assembly connected to the housing to receive materials dischargedfrom the mixing chamber, an inlet passage on the `housing for deliveringmaterials to -be mixed into the mixing chamber, a header having fourseparate inlet ports and a single outlet port, means connecting theoutlet port of the header to the inlet passage to the mixing chamber,the header hav-ing first and second internal passageways for supplyingreactive materials to said outlet -port of the header, the first of saidinternal passageways extending from a first inlet port to the headeroutlet and the second of said internal ways to said outlet port of saidheader, said third passageway extending from the first inlet port to athird inlet port and the fourth passageway extending from the secondinlet port to a fourth inlet port, and means including valve means forcontrolling flow into each of said header inlet ports.

7. Mixing and spraying apparatus comprising a housing having acylindrical bore defining a mixing chamber, a rotor 'mounted coaxially`within the bore, said rotor having a plurality of axially spaced ringseach having a series of wedge-shaped blades thereon, a power-drivenshaft extending into the bore for rotating the rotor, an inlet on thehousing for delivering materials to be mixed into the mixing chamber, anozzle assembly connected to the housing to receive materials dischargedfrom the mixing chamber, a header having four separate inlet ports and asingle outlet port, means connecting the outlet port of the header tothe inlet passage to the mixing chamber, the header having rst andsecond internal passageways for supplying reactive materials to saidoutlet port of the header, the rst of said internal passagewaysextending from a first inlet port to the header outlet and the second ofsaid internal passageways extending from a second inlet port to saidheader outlet, and the header having third and fourth internalpassageways for respectively supplying air and a solvent through saidrst and second internal passageways to said outlet port of said header,said third passageway extending from the rst inlet port to a third inletport and the fourth passageway extending from the second inlet port to afourth inlet port.

References Cited by the Examiner UNITED STATES PATENTS 3,035,775 5/1962Edwards et al. 239-142 3,123,306 3/1964 Bradley 239--336 3,229,9ll1/1966 Carlson et al. 239-142 EVERETT W. KIRBY, Primary Examiner.

1. MIXING AND SPRAYING APPARATUS COMPRISING A HOUSING HAVING ACYLINDRICAL BORE DEFINING A MIXING CHAMBER, A MIXER ROTOR MOUNTEDCOAXIALLY WITHIN SAID BORE, THE ROTOR COMPRISING A PLURALITY OF AXIALLYSPACED RINGS EACH HAVING A SERIES OF WEDGE-SHAPED BLADES FIXED ON THEPERIPHERY THEREOF, THE BLADES HAVING RUNNING CLEARANCE WITHIN SAID BORE,THE BLADES ON ADJACENT RINGS BEING CIRCUMFERENTIALLY STAGGERED, A POWERDRIVEN SHAFT PROJECTING INTO THE BORE FOR ROTATING THE ROTOR, MEANS FORINTRODUCING LIQUID MATERIALS UNDER PRESSURE INTO THE MIXING CHAMBER,